Any cooked meat= sandwitch. However, it provides only 50 percent of every product. Members should have an option to add butter. Sandwitch can be cooked on stove only giving marginally more hp than original. Now doesn't work on a few RuneScape gold fish. Everything should be burnable! Metal can be extracted using Superheat spell only and it is always the cheapest metal (if oplayer joins gold, superheat will extract copper). Clay+bucket= unusable bucket. Clay is supposed to be glued. Any melee weapon+any arrow destroyed arrow. Player is designed to cut off arrow heads.
Any meals + any neutral NPC = a word of gratitude. Neutral NPS may be men and girls, guards, and various bot-like npcs (doomsayer, duke of Lumbirdge etc). Any item (jewelry, armor)+shield = salute from the guards around. Thing is seen only, guards can't drop it. Player cannot provide armor or weapons reduced in level than guards (if guards should wield steel firearms, copper and iron can't be offered)
Cash + non agressive npc = commerce. Farmers can offer an advice or a product (shears, axe, bucket), guys - some tools, girls - a few clothes. Once item is shown, npc can't drop it. Any dye + sheep = colored sheep. All rams begin attacking player and sheep returns to normal a while later. That's almost all.
Most of the skills in Old school rs gold don't have too much'skill' involved. I would like to suggest mini games which in fact need more ability. These mini games won't just demonstrate that a man or woman is really'proficient' but they will also provide an enjoyable alternative to regular training.